pollution. pollution defined as something that is unwanted that interferes with the environment and...
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Pollution
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Pollution defined asSomething that is unwanted that interferes with the environment and an organisms self sustaining processes in a negative way- The textsA change in the physical chemical and biological characteristics of air water and food that adversely effects the survival of organisms.
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Basic Toxicology
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Basic ToxicologyToxin=Damages a living organism by ingesting or absorbed.Toxicity=the degree which a toxin harmful. Any thing in high enough quantities may be harmfulEx water
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Factors to considerDosage Amount of exposure Size and age or organismAbility of organism to detoxifySensitivity to substanceSynergistic/Antagistic effects
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Dose response analysis 2 tests LD 50 when 50% die Poisons-LD50= 50 mg or lessThreshold dose=when a negative effect occurs
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Types of effects Acute-Short exposure to a high level of toxinEx snake biteChronic-Long term exposure to a low level toxin.
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Risk assessment/management Assessment calculations of the risk takenManagement=strategies taken to reduce risk
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Air Pollution
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Air Pollution 2 sources human and naturalNatural=volcanoCar=man The majority of the pollution today is from man and occurred after the industrial revolution.
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Beijing is one of the most polluted cities
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SourcesPrimary pollutants released directly into the lower atmosphere and are toxic.Ex mercury coal burning Secondary-toxins formed in the atmosphere from multiple primary pollutants.SO2 from coal +H2O H2SO4
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EPAEnvironmental Protection AgencyRegulates pollutionRegulates 6 Criteria PollutantsCarbon monoxide CO-combustion-60% carLead Pb-from coal and smeltingOzone O3-good in stratosphere-bad in troposphere-from combustion.Nitrogen Dioxide NO2-car engines forms nitric acid Sulfur dioxide SO2 coal and dieselsulfuric acid Particulates
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ChangesSince 1970 CO and lead have decreasedNew concerns=VOC volatile organic compounds.Toxic organic compounds from manufacturing, dry cleaning, industrial solvents, form O3
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SmogFog=natural water vaper2 types industrial and photochemicalSmog=Toxic gas
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Industrial Smog
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Industrial (grey) smog- formed from the burning of coal common 1900-1950.CO2 combines with particulate matter. Problems=Sulfuric acid lead particulate matter.Lead to- pneumonia, tuberculosis,heart failure, bronchitis, whooping cough. 1952 killed 4000 in London
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Photochemical smog
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Photochemical Smog.The brown cloud found on sunny days. Caused by car combustion and industrial combustion.VOC, NOx, O3 combine, catalyzed by sunlight, to form a toxic gas. Common in baltimore
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InversionAir is trapped by warmer layers of air in low places.
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Climate change
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Caused By Increasing CO2 and other green house gasses cause the green house effect.1900-1950 25% caused by combustion 75% by reducing biomass.1950-today 75% by combustion 25% by reduction in biomass.
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IPCC (Intergovernmental panel on climate change) report 1-Climate change is occurring There is a correlation between temperature and CO2 levels (greater than 90%)CO2 1950 280ppm 2006 380ppmMethane 1950 715ppm 2005 1774ppmNOx 270-319
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Rise in CO2
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EffectsAdditive effect decrease in ice caps= increased temperatures.Increased heat = increased H2O gas=increased heat.Increased temp=less permafrost=more Co2 released from the permafrost.Increased temp= decreased land= less biota and more CO2
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ImpactHigher levels of water-maryland 4th most at riskDecreasing glaciers=less drinking waterIncreased storms
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Ozone depletion
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Ozone depletion Ozone in stratosphere is a toxin but in the stratosphere provides a defense from UV radiation. Formation 3O2 + UV sunlight 2O3
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Ozone depletionOccurs during the summer months. Caused by Chloroflurocarbons (CFCs) And other compoundcompounds used in propellants, fire extinguishers, and hair spray.
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Reaction CFCs break down to Chlorine gas and reacts with ozone Cl + O3 O2+ClOis stored in ice crystals over the winter.In the spring the crystals melt and continue to reactClO+O Cl+O2
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Results26 million square Km zone of thinness (hole).Chronic Exposure= eye cataracts, skin cancer, weakening of immune system.Kill phytoplankton,-primary producers.
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Acid rain
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Acid rain:Formed from SO2 and NOx and water into sulfuric and nitric acidspH=range from 5.4-2.3Caused by coal and auto emmissions
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Environmental effectsMineral leachingSulfur and nitrogen buildup in soil/lakesIncreased aluminum buildupLeaching of calcium from conifersLowering of pH in lakesHuman respiratory irritationDissolving stone-monuments buildings exc.
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2 types Dry acidic particle deposition-drops few days afterWet deposition-drops 4-14 days1990 Clean air Act reduced SO2 and NOx levels.
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